It is very important to get the right size. I recently bought my son an Osprey Talon 33, he had his heart set on it.
Go Outdoors has them in stock, so off we went, he put on the L/XL and walked around a bit saying how great it felt, and that he had made his mind up. Good job I was there, because it was too big for him, so we changed to a M, and it’s perfect. I could clearly see the shoulders were not sitting correctly, despite altering it.........He loves his Talon, 👍😀